Fixed panic when providing a CLI command with an incorrect JSON input (#3398)

## Changes
Fixed panic when providing a CLI command with an incorrect JSON input

## Why
CLI should not panic but show a nicer, more actionable error instead.
Fixes #3393

## Tests
Added an acceptance test

Author: andrewnester

NEXT_CHANGELOG.md

@@ -9,6 +9,7 @@
 * Update Go SDK to 0.79.0 ([#3376](https://github.com/databricks/cli/pull/3376))
 
 ### CLI
+* Fixed panic when providing a CLI command with an incorrect JSON input ([#3398](https://github.com/databricks/cli/pull/3398))
 
 ### Bundles
 * Changed logic for resolving `${resources...}` references. Previously this would be done by terraform at deploy time. Now if it references a field that is present in the config, it will be done by DABs during bundle loading ([#3370](https://github.com/databricks/cli/pull/3370))

acceptance/bundle/variables/file-defaults/output.txt

@@ -41,7 +41,7 @@
 
 === file cannot be parsed
 >>> errcode [CLI] bundle validate -o json --target invalid_json
-Error: failed to parse variables file [TEST_TMP_DIR]/.databricks/bundle/invalid_json/variable-overrides.json: error decoding JSON at :0:0: invalid character 'o' in literal false (expecting 'a')
+Error: failed to parse variables file [TEST_TMP_DIR]/.databricks/bundle/invalid_json/variable-overrides.json: error decoding JSON at [TEST_TMP_DIR]/.databricks/bundle/invalid_json/variable-overrides.json:1:1: invalid character 'o' in literal false (expecting 'a')
 
 
 Exit code: 1

acceptance/cmd/workspace/create-scope/out.test.toml

@@ -0,0 +1,5 @@
+Local = true
+Cloud = false
+
+[EnvMatrix]
+  DATABRICKS_CLI_DEPLOYMENT = ["terraform", "direct-exp"]

acceptance/cmd/workspace/create-scope/output.txt

@@ -0,0 +1,27 @@
+
+>>> musterr [CLI] secrets create-scope --scope-backend-type AZURE_KEYVAULT --json "scope": "xxxxxxxx-xxx"
+Error: error decoding JSON at (inline):1:8: unexpected additional content
+
+Exit code (musterr): 1
+
+>>> musterr [CLI] secrets create-scope --scope-backend-type AZURE_KEYVAULT --json ["scope"]
+Error: expected JSON object, received sequence
+
+Exit code (musterr): 1
+
+>>> [CLI] secrets create-scope --scope-backend-type AZURE_KEYVAULT --json {
+  "scope": "xxxxxxxx-xxx",
+  "scope_backend_type": "AZURE_KEYVAULT",
+  "keyvault_metadata": {
+    "dns_name": "test",
+    "resource_id": "123456"
+  }
+}
+Warning: unknown field: keyvault_metadata
+  in (inline):4:4
+
+
+>>> [CLI] secrets create-scope --scope-backend-type AZURE_KEYVAULT --json {
+  "scope": "xxxxxxxx-xxx",
+  "scope_backend_type": "AZURE_KEYVAULT"
+}

acceptance/cmd/workspace/create-scope/script

@@ -0,0 +1,17 @@
+trace musterr $CLI secrets create-scope --scope-backend-type AZURE_KEYVAULT --json '"scope": "xxxxxxxx-xxx"'
+
+trace musterr $CLI secrets create-scope --scope-backend-type AZURE_KEYVAULT --json '["scope"]'
+
+trace $CLI secrets create-scope --scope-backend-type AZURE_KEYVAULT --json '{
+  "scope": "xxxxxxxx-xxx",
+  "scope_backend_type": "AZURE_KEYVAULT",
+  "keyvault_metadata": {
+    "dns_name": "test",
+    "resource_id": "123456"
+  }
+}'
+
+trace $CLI secrets create-scope --scope-backend-type AZURE_KEYVAULT --json '{
+  "scope": "xxxxxxxx-xxx",
+  "scope_backend_type": "AZURE_KEYVAULT"
+}'

acceptance/cmd/workspace/create-scope/test.toml

@@ -0,0 +1,10 @@
+Local = true
+Cloud = false
+
+[[Server]]
+Pattern = "POST /api/2.0/secrets/scopes/create"
+Response.Body = '''
+{
+    "scope": "xxxxxxxx-xxx"
+}
+'''

libs/dyn/jsonloader/json.go

@@ -23,8 +23,19 @@ func LoadJSON(data []byte, source string) (dyn.Value, error) {
 		if err == io.EOF {
 			err = errors.New("unexpected end of JSON input")
 		}
-		return dyn.InvalidValue, fmt.Errorf("error decoding JSON at %s: %v", value.Location(), err)
+		// Get the current offset for error reporting
+		errorOffset := decoder.InputOffset()
+		errorLocation := offset.GetPosition(errorOffset)
+		return dyn.InvalidValue, fmt.Errorf("error decoding JSON at %s: %v", errorLocation, err)
 	}
+
+	// Check if there are any remaining tokens (should not be valid JSON)
+	if decoder.More() {
+		errorOffset := decoder.InputOffset()
+		errorLocation := offset.GetPosition(errorOffset)
+		return dyn.InvalidValue, fmt.Errorf("error decoding JSON at %s: unexpected additional content", errorLocation)
+	}
+
 	return value, nil
 }
 

libs/dyn/jsonloader/json_test.go

@@ -91,3 +91,23 @@ func TestJsonLoaderEOF(t *testing.T) {
 	_, err := LoadJSON([]byte(eofData), "path/to/file.json")
 	assert.ErrorContains(t, err, "unexpected end of JSON input")
 }
+
+const mapWithNoBraces = `
+"job_id": 123,
+"new_settings": {
+    "name": "xxx",
+    "wrong": "xxx",
+}
+`
+
+func TestJsonMapWithoutBraces(t *testing.T) {
+	_, err := LoadJSON([]byte(mapWithNoBraces), "path/to/file.json")
+	assert.ErrorContains(t, err, "error decoding JSON at")
+}
+
+const validInline = `["job_id", 123]`
+
+func TestJsonValidInline(t *testing.T) {
+	_, err := LoadJSON([]byte(validInline), "path/to/file.json")
+	assert.NoError(t, err)
+}

libs/flags/json_flag.go

@@ -57,6 +57,27 @@ func (j *JsonFlag) Unmarshal(v any) diag.Diagnostics {
 		return diags
 	}
 
+	if !nv.IsValid() {
+		kind := reflect.TypeOf(v).Kind()
+		if kind == reflect.Ptr {
+			kind = reflect.TypeOf(v).Elem().Kind()
+		}
+
+		expectedJsonType := "string"
+		switch kind {
+		case reflect.Struct, reflect.Map:
+			expectedJsonType = "object"
+		case reflect.Slice:
+			expectedJsonType = "array"
+		}
+
+		return diags.Append(diag.Diagnostic{
+			Severity: diag.Error,
+			Summary:  "Invalid command input",
+			Detail:   fmt.Sprintf("expected JSON %s, received %s", expectedJsonType, dv.Kind()),
+		})
+	}
+
 	// Then marshal the normalized data to the output.
 	// It will serialize all set data with the correct types.
 	data, err := json.Marshal(nv.AsAny())